package org.apache.rocketmq.client.consumer;

import org.apache.rocketmq.common.message.MessageQueue;

import java.util.Set;

/**
 * A MessageQueueListener is implemented by the application and may be specified when a message queue changed
 */
public interface MessageQueueListener {
    /**
     * @param topic      message topic
     * @param mqAll      all queues in this message topic
     * @param mqAssigned collection of queues, assigned to the current consumer
     */
    void messageQueueChanged(final String topic, final Set<MessageQueue> mqAll, final Set<MessageQueue> mqAssigned);
}
